We arrive at Las Tecas camp on a motorbike, I see it cut off from the jungle in the distance, an open space surrounded by a series of wooden frames, covered with huge tarpaulins.
Below, there are more than a hundred colorful backpack-style pop-up tents and dozens of hammocks hanging from the wooden poles.
As we approach we see hundreds of people chatting, playing dominoes or sitting outside what I can only describe as an internet cafe in the jungle.
This is northern Colombia. We are in the middle of nowhere and there is electricity from a noisy generator on the side of the hill, makeshift shops, cafes, running water and clean toilets and showers – although ‘they charge a dollar per pop for almost everything, and some here can’t afford that.
Las Tecas is an organized slum with a few extras.
I visited more refugee camps, transit camps and migration centers than I can count, but this level of organization took me by surprise.
The reason is money. The camp is operated by an extensive network of smugglers and its clients are migrants heading north to the United States.
Ahead of them is a thick jungle infested with poisonous snakes, spiders, insects, criminal gangs, terrorist groups, and a 65-mile trek through rivers and mountains.
This is the Darien Gap – the gateway to Panama from Colombia and the gateway to the United States of America.
For migrants, their last night in this camp is their last night of safety for a while.
If Everest has a base camp, the gap has Las Tecas.
We put on our hammocks before dark and strolled among the migrants, explaining that we were going to join them for part of their journey.
They come from all over the world – Nepalese, Africans, Asians, Haitians, but especially South Americans.
They were friendly and seemed both excited and nervous. What struck us all was the number of families and the quite extraordinary number of small children.
I’ve read about the Darien Gap for years, and the only reasonable conclusion anyone would come to is that it’s too dangerous to walk through as an adult, let alone as a child. .
But the flow of migrants attempting this crossing is equally remarkable.
In the first nine months of this year, 150,000 people did. More than 20,000 of them were children. Ten years ago, barely 200 migrants attempted it.
Smugglers facilitate these daily trips and make a fortune.
The migrants are desperate, and one can only imagine how awful their home life must be to face this nightmare that takes at least five days in scorching heat and crushing humidity.
I’ll be honest, I was a bit scared and only tried a small part of the trip.
At 4 a.m. the next morning, the camp is awake, tearing down tents and packing up whatever they can carry.
Moms and dads get their kids ready, get them dressed, give them breakfast, pack their little backpacks and put on their colorful rubber boots.
A baby had been bitten by insects during the night. She was covered in bites and her mother was scratching her back to try to calm the itching.
They haven’t even arrived in the jungle yet.
At first light, they gather to receive instructions from a man speaking on a loudspeaker.
Then a door opens, and they rush in.
One of their first obstacles among many others is a river, and a few minutes after the start, everyone is wet.
Sliding over rocks underwater, cubs grab their parents, parents grab their children, hoist them up on their backs and shoulders to try to keep them dry.
But everyone keeps moving.
We cross the rivers following the migrants who walk along the bottom of the valley towards the heights. It takes them at least a day.
Against my usual judgement, like many here, our guides tell us to wear wellington boots.
The reason for this is that if you step on a snake it bites back and if you think about it, it’s pretty much at the calf muscle.
Here you wouldn’t last more than 30 minutes after a really nasty snakebite, so we took the boot option.
The problem is that we’re wading through rivers, so every 10 minutes or so you’re carrying two extra water boots – and trust me, they’re heavy.
I was shown how to lean against a tree and bend my knee towards my back to drain the water. Simple, but boring, although I now accept that the common wellie really can be a lifesaver.
Michael Zambrano from Venezuela carries his sleeping two-year-old son, Lucien, in a baby carrier on his chest, and a heavy bag on his back.
Her four-year-old son, Jordan, remains close to his parents. Mom – Mariangela – is seven months pregnant. They are expecting a daughter and have already named her Ana.
This family has been walking for months.
They left Venezuela seven years ago, lived in Chile for a while, then came to Colombia, where Michael worked as a street artist, earning enough money to continue their journey north.
The family is towards the back of the group.
“We have to save our energy and go slow,” Michael told me.
“I have this backpack plus my baby, so it’s more difficult, but this one is four, so he’s at least able to walk,” he continued, pointing to Jordan.
From time to time, another Venezuelan migrant, Eduardo, whom the family met on the trail, helps them, lifting the little boy on his shoulders into the deeper waters.
Along the route, wooden signs nailed to the trees invite them to do so.
One reads ‘Do not be afraid’, another ‘Difficulties disappear in the face of courage’.
But the jungle is full of deadly snakes, spiders and insects. It is scorching hot and humid.
And very quickly the migrants become rare, the youngest and the strongest leave behind them the weakest.
The last of the group is a woman who has already sprained her ankle, it happened in the first hour.
She now uses a stick for support. Her husband stops her from time to time and takes her boots off to drain the water and check for swelling. And then they continue.
It is impossible to imagine that she will get there. But she continues.
They know they have to climb the top of at least one huge mountain, but the whole journey is arduous.
Rivers can surge if the rain is heavy, and it can just lead to people’s death, especially if they can’t swim, which many can’t.
The first big challenge our group encounters, after the river, is a high hill made entirely of mud and rock.
It’s steep and it’s like dripping clay. Migrants must recover to continue their journey.
Simple wooden steps were hewn out of the mud, with ropes to keep people from falling into a ravine.
Without these steps their passage would take hours.
My rubber boots sank all the way to the top in the mud as I pulled myself up. At the top, a narrow gap has been carved out between the mud-covered rock that only one person at a time can cross.
I make my way before descending the muddy staircase, slipping and sliding, and holding the rope for my life.
All I think is if I’m fighting how can anyone carry around everything they own plus their kids even remotely manage this?
And yet they plod through foot-deep mud.
Some of the men grunt as they climb up and down the steep embankment, the women and children look terrified.
We meet Carlos Chinchin rinsing his boots and hands in the river water after crossing the muddy hill.
Strapped to her back is her toddler Carlito, a Spiderman sun hat on her head.
Carlos is from Ecuador. His wife and their second child have already made the crossing and are in the United States.
I ask them where they are in the United States, he says he doesn’t know.
“They only told me they were in a safehouse…” he replied.
It must be heartbreaking to carry such a small child through the jungle, but Carlos says he’s driven by his desire to see his wife Catherine and his child’s desire to see his little brother Josue.
As he leaves, he sings to Carlito, calms him and comforts this little boy who cannot know what is going on.
A few hours later, we meet Michael again. He looks tired this time – the family has just been navigating through the mud.
It’s hard, he says, but he has faith.
“There is nothing stronger than God, he will give us the strength to get through all the mud in front of us.”
That’s a remarkable confidence given that the US border is now closed to Venezuelans.
The recent change in border policy means many Venezuelans are now stranded in countries along the migration route, unsure of where to go.
Michael’s is one of them, but they’re determined to keep going. He says he thinks Americans will understand his situation and have mercy.
But they continue. This is a huge movement of people that is only expected to grow.
And it’s hard to see how it’s going to end.
Dominique Van Heerden, Gustavo Aleman and Carlos Villalon, producers
Richie Mockler, cameraman